Book excerpt: Heteropolyacids as Highly Efficient and Green Catalysts Applied in Organic Transformations introduces heteropolyacids (HPAs) as promising candidates for use as green catalysts. This book initially presents an overview of chemistry of HPAs, including the history of their discovery and applications, systematic classifications, solubility, coordination and binding chemistry, isomerization, stability, redox activity, acidic properties, basicity, skeleton structure, structure types, self-assemblage, surface area, electrochemical behavior, methods of investigation, and characterization. Other sections present and compare the applications of HPAs as homogeneous and heterogeneous catalysts. The book provides readers with a basic-to-advanced range of knowledge on how useful and green HPAs can be used for use as catalysts in organic transformations and even the synthesis of complex organic molecules. - Focuses on applications of HPAs as catalysts, but also includes basic information on HPAs to make it useful to those researchers and scientists whose activities are focused on biochemical analysis, electrochemistry, electrochemical devices, protection of corrosion, medicine and photo-catalyzed reactions - Includes a subdivision devoted to HPA-catalyzed multicomponent reactions for the synthesis of some biologically active compounds via a double-green strategy - Illustrates reactions with approximately 100 chemical reaction schemes to aid understanding